Electrical m etal-h eater



(No Model.) 2 Sheets-Sheet 1.

G. D. BURTON. ELECTRICAL METAL HEATER.

No. 475,181. Patented May 17,1892.

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(No Model.) 2 Sheets-Sheet 2.

G. D. BURTON.

. ELECTRICAL METAL HEATER. No. 475,181. Patented May 17,1892.

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R d m I ll g'lH I r 1 H i 2 D11 1 b E Ts WITNESSES l \l e Z a 1% UNITEDSTATES PATENT OFFICE,

GEORGE D. BURTON, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE ELECTRICALFORGING COMPANY, OF MAINE.

ELECTRICAL METAL-HEATER.

SPECIFICATION forming part of Letters Patent No. 475,181, dated May 17,1892.

Application filed May 26, 1891. Serial No. 394,108. (No model.)

To all whom it may concern:

Be it known that I, GEORGE DEXTER BUR- TON, a citizen of the UnitedStates, residing at Boston, in the county of Suffolk, in the State ofMassachusetts, have invented certain new and useful Improvements inElectric Apparatus for Making Metal Forgings, of which the following isa specification.

The object of this invention is to produce metal forgings of superiorquality in an economical manner, and especially to prod ucc twistedmetal bars by the aid of electricity for stair-rods, fence-pickets, andornamental metal-work in general.

Figure 1 of the accompanying drawings represents a side elevation ofthis improved apparatus in connection with an electric converter. Fig. 2representsa plan view thereof. Fig. 3 represents a face view of theoscillating clamp for holding one end of the bar to be twisted. Fig. 4represents a portion of a twisted bar.

Similar numerals of reference indicate corresponding parts in thediiferent figures.

The rings 10 and l1,where0f segments only are representedin thedrawings, constitute parts of an electric-current converter, which neednot be fully illustrated in this case. The ring 10 is provided with aboss 12 and the ring 11 with a boss 13, which bosses constitute theterminals of the converter. Abracket 20, composed of copper or othersuitable conductive material, is attached at one end to the boss of thering 10, and depends therefrom when arranged as shown in the drawings. Asimilar bracket 30, also composed of copper or other suitable conductivematerial, is attached to the boss or terminal 13 of the converter-ring11 and depends therefrom. The outer ends of these brackets are providedwith arms 21 and 31, respectively, which are preferably slottedlongitudinallyand adjusted in line with each other in the samehorizontal plane. The brackets and arms may be composed wholly or inpart of iron or other material or composition of lower conductivity thancopper, provided they be sufficiently large in proportion to the bars tobe operated upon to carry a current adapted to heat such bars to aforging temperature without becoming overheated themselves.

Two clamps 40 and 50, composed of copper, iron, or other suitableconductive material, are adjustable, respectively, on the arms 21 and31. These clamps or holders may be of any suitable construction forclamping the ends of the bar to be heated and twisted.

A bar-twisting apparatus is disposed on the arm 31. This bar-twistercomprises two similar adjustable standards and 61, a shaft 70, journaledin said standards, and a clamp 71 at one end of said shaft for graspingone end of the bar to be twisted. A third standard 62, somewhat tallerthan the shaft-supporting standards, is disposed at the outer end ofsaid arm 31. A stub-shaft 80 is journaled in said standard 62, andprovided at one end with a beveled pinion 81 and at the other end withan actuating-crank S2. The outer end of the shank is provided with abeveled gear '72, which meshes with the pinion 81 on the stub-shaft 80.The clamp 71 comprises a rectangular frame 73, two sliding jaws 74 and75, and set-screws 76 and 77, passing through the ends of said frame andengaging said jaws for adjusting them upon the end of the bar.

The standards 60, 61, and 62 are severally provided with lugs 63,whichproject downward through the slot in the arm 31, and said arm isprovided at its outer end with a fixed dependent lug (it, having aninsulating-bushing 65. A screw-rod 66 passes through the bushing 05 andthrough the lugs 63, and is provided with a hand-wheel 67 at its outerend. This screw-rod serves to adjust the twister on the arm 31.

In the use of this apparatus one end of a metal bar 100 to be twisted isplaced in the clamp 40 and the other end in the clamp 50, said barextending through the clamp 50 and the extended end thereof beingengaged by the jaws of the clamp '71. Both the clamps 40 and 50 areclosed tightly upon the bar and the electric current switched on. Thecurrent passes from the positive ring 10 of the converter through thebracket 20 or other conductor leading from said ring, thence through thearm 21, thence through the clamp 40, thence through the bar 100 to beheated to the clamp 50, thence through the arm 31 to the bracket 30, andthrough said bracket or its equivalent to the negative ring 11 of theconverter. The rod 100, under the action of the heating-current, will beheated in a few seconds to a forging temperature throughout that portionof its length which spans the space between the clamps and 50, while theends which are directly in contact with the clamps will remain cool inthe metallurgical sense of t he term. The currentisthen switched off andthe clamp released from the bar. The crank 82 is then turned, wherebythe shaft and its clamp 71 are rotated, one end of the bar being stillheld in the clamp 40 and the other end in the clamp 71. The rotation ofthe shaft 70 causes a twisting of the bar, as represented in Figs. 1, 2,and 4. The bar may be twisted more or less, as desired, and is thenreleased from the clamps and removed from the apparatus.

In the use of the electric currentfor heating bars or blanks, I havefound that the bar or blank is heated from the interior instead of theexterior, as in the ordinary furnace-forge, and that there are no gasesintroduced into the metal when heated by electricity, and consequentlywhen twisted no scale is formed and the metal is left clean and freefrom blem ishes. Moreover the bar retains the heat de- \V hen heatedfrom the exterior,

the outer surface of the metal is broken, which causes the scale, owingto the fact that the exterior is overheated before the interior isheated to the required working temperature.

I claim as my invention-- 1. In an electric metal-working apparatus, thecombination of two converter-rings constituting the positive andnegative poles, two conductive brackets connected, respectively, to saidrings and provided with horizontal arms, two clamps adjustable towardand fro m each other on said arms, two standards on one of said arms, ashaft journaled in said standards and provided with a clamp at one end,and means for rotating said shaft.

2. In an electric metal-working apparatus, the combination of twoconverter-rings eonstituting the positive and negative poles, twoconductive brackets connected, respectively, to said rings and providedwith horizontal arms, two clamps adjustable toward and from each otheron said arms, two standardson one of said arms, a shaft journaled insaid standards and provided with a clamp at one-end, means for rotatingsaid shaft, and means for adjusting said standards on said arm.

GEO. D. BURTON.

Witnesses:

CHAS. F. ADAMS, F. C. SOMES.

